Harbor Foam EPS meets or exceeds the requirements of ASTM C578. The American Society for Testing and Materials (ASTM) has developed the Standard Specification for Rigid Cellular Polystyrene Insulation Thermal Insulation, C578. This provides EPS manufacturers as well as specifiers with the types, properties, dimensions, sampling, test procedures, and ordering instruction for EPS foam insulation. The Physical Properties table below indicates the minimal requirements for each classification. Specifiers can use this information to accurately determine the type of EPS needed to meet the required energy codes so manufacturers can easily provide the appropriate product without confusion or problems.

Source: EPS Industry Alliance, 2020,